1. Field of the Invention
This invention relates to electric vehicles and in particular to means for controlling and indicating the temperature condition of the electric drive motor of the vehicle.
2. Description of the Prior Art
In the conventional electrically controlled vehicle, the operation of the vehicle is controlled by suitable means, such as an accelerator pedal, to vary the amount of current to the electric drive motor and, thus, the power developed thereby. At times, the vehicle operator may require that the motor develop a high power, such as during acceleration or climbing grades, etc. It is desirable to permit such high power operation for a period of time while yet preventing the continuing of such high power operation to the extent that the motor becomes overheated and, thus, is damaged.
As a concomitant of such desideratum, it is desirable to provide some indication to the vehicle operator of the temperature condition of the motor so as to advise the operator as to the possible impairment of the system capabilities resulting from high power operations causing an elevation in the temperature of the motor.
One improved form of electrically propelled vehicle illustrating a control for controlling the operational speed of the vehicle is disclosed in U.S. Pat. No. 4,008,423 of Clinton C. Christianson et al, which patent is owned by the assignee hereof.